Device for adjusting grinding disks



0. WALDRICH DEVICE FOR ADJUSTING GRINDING DISKS Aug. 1 1, 1964 2 Sheets-Sheet 1 Filed Sept. 14, 1962 INVENTOR OSKar Wald/(ch I A'r'r iq uess Wm ow 1 |y| lilll Aug. 11, 1964 o. WALDRICH DEVICE FOR ADJUSTING GRINDING nxsxs 2 Sheets-Sheet 2 Filed Sept. 14, 1962 INVENTOR OSKCLI" Wald/126 SLAM J ArrorLNEg;

United States Patent 3,143,832 DEVICE FOR ADJUSTING GRINDING DISKS Oskar Waldrich, Hohier Weg 1, Siegen, Westphalia, Germany Filed Sept. 14, 1962, Ser. No. 223,706 Claims priority, applicatien Germany Feb. 13, 1962 1 Claim. (Cl. 51-165) This invention relates to a device for continuously compensating the wear of grinding disks of roller grinding machines.

Whenever a roller is ground in a roller grinding machine, the first step is to set the depth of the cut. The grinding continues from one end of the stroke to the other end with this set thickness of cut. However, since the grinding disk is used up during lengthy operational movements, while the feed toward the workpiece takes place only at the end of a stroke but not during the stroke itself, the feed and thus the depth of the cut change during the stroke. Since the feed takes place at both stroke ends, the wear of the grinding disk is particularly pronounced in the middle of the grinding stroke, with the result that a work piece with a bulging outer surface is produced.

Experienced grinders are familiar with this effect and attempt to provide some form of compensation by manual adjustment during the stroke movement. Obviously, such attempts can not attain the desired results since the operation of the feeding device is too coarse to follow a continuous manual adjustment during the entire stroke; the adjustment actually takes place at interrupted time intervals and thus the outer surface of the roller receives a step-like form.

In order to produce a precisely cylindrically ground roller despite the fact that it has been ground in the abovedescribed manner, it is necessary to increase the duration of the finishing operation since the finishing then serves not only for producing a polished surface, but also for the elimination of the described bulging of the outer surface of the roller.

An object of the present invention is to eliminate these drawbacks of prior art grinding.

The present invention is also based on the realization that the wear of the grinding disk does not depend only upon the relation of the material of the work piece to the grinding material, but also upon the cross section of the cut. The smaller the cross section of the cut, the smaller will be the deviation of a work piece from its correct cylindrical form.

Furthermore, a substantial initial feed is necessary in order to provide an economically acceptable output during grinding and to secure such economic effect at the end of the stroke. This great initial feed further increases the wear of the grinding disk, whereby the lack of uniformity in the shavings becomes greater, so that the work required for the finishing and particularly the duration of the finishing operation are greatly increased.

A study of the output of the main motor driving the grinding disk indicates that in the case of the above described prior art methods the initial output drops approximately to the extent of 65 A further object of the present invention is to eliminate these drawbacks.

In accomplishing the objects of the present invention it was found advisable to provide an attachment to roller grinding machines which would make possible continuous compensation for the wear of grinding disks, said attachment incorporating a continuously operating device for forwardly or rearwardly setting the carrier of the grinding disk relatively to the work piece, whereby the extent of the forward or rearward adjustment may be set depend- 3,143,832 Patented Aug. 11, 1964 ing upon changes in the output of the motor driving the polishing disk, which is the main motor.

In its simplest embodiment this continuous adjustment does not vary throughout the entire stroke, and is so set that the output of the main motor remains essentially the same. However, it is also possible to provide a regulating device wherein the output of the motor will constitute the measure for the continuous feed. However, an arrangement of this nature is, on the one hand, more expansive than a device in accordance with the present invention wherein the drive of the feed device takes place, for example, manually through the use of a potentiometer and by means of a direct current motor having a strong field and regulatable within wide limits; on the other hand, the above-described arrangement has the drawback that it already presumes the form of the roller to be ground to be cylindrical. Otherwise, since the thickness of the cut remains the same, any possible non-uniformity in the shape of the outer surface of the roller will be retained during the grinding. Thus again a non-uniform shape would be produced. Nevertheless, it may be advantageous in the course of rough turning during the last feed to give up regulation by means of the main motor and to operate with a continuously varying feed. However, it is also possible to introduce a damping device which will balance the differences, into the regulating means between the output drive of the main motor and the continuous feed drive of the present invention. Similar considerations are effective in case the roller to be ground consists of different materials having different hardnesses. Furthermore, the copying properties of the described regulation of the continuous feed of the present invention may be effectively utilized, for example, for the regrinding of bulging or hollow shafts.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawing, showing, by way of example only, a preferred embodiment of the inventive idea.

In the drawings:

FIGURE 1 is a side view, partly in section, showing a grinding wheel support of a roller grinding machine.

FIGURE 2 is a view of the support shown in FIG. 1, looking from the side of the work piece.

The drawings show a grinding machine having a bed 5. A support 6 is mounted upon the bed 5 and is movable in the longitudinal direction upon a V-shaped guide 7 and a horizontal flat guide 8. An upper support 9 is slidably mounted upon the support 6; it is guided by V-shaped guides 10 and actuated by a feed spindle 11 (FIG. 2).

A quick mechanical feed of the upper support 9 can be carried out by means of a motor 12 driving a gear wheel 13 connected with a worm 14 meshing with a worm gear 15 which is connected with the feed spindle 11.

A rough preliminary manual adjustment in the same direction can be effected by a hand wheel 16 actuating spur wheels 17 which drive a pair of cone gears 18 connected with a shaft 19, actuating a worm drive 20 upon a shaft 21 which transmits the drive over a further worm drive 22 to feed spindle 11 (FIG. 2).

The bulge-turning device is connected with a carrier 26 which is pivotally mounted upon the upper support 9 and which carries the grinding disk 27. The carrier 26 is swingable about the axis of the shaft 21. The swinging of the carrier 26 is accomplished by an eccentric 28 acting upon a ram 29 which engages a roller 30 carried by an angular lever 31. The lever 31 is pivoted at 32 upon the upper support 9 and has a horizontally extending arm 33 provided with a sliding surface 34.

The carrier 26 supports for rotation a spindle 37 which is connected with a spindle 35 by a worm drive 36 and which moves a support 38 along a guide 39. The support 38 carries a roller 38 which rolls upon the sliding sur- 7 =3 face 34 of the lever 31 as soon as the support 38 is moved.

Due to this arrangement it is possible to adjust the pitch of the bulge of a grinding disk, namely, the further the roller 38' moves to the left (looking in the direction of FIG. 1), the greater is the pitch, and vice versa.

The manual fine adjustment of the grinding disk is carried out by a hand wheel 23 the rotation of which is transmitted by means shown in FIG. 1 of the'drawings to a gear'24 and a fine adjustment shaft 25 formed as a pin shaft and rotatably carried by the support 38; the shaft 25 is movable longitudinally in the hub of the gear 24 which is mounted in the grinding disk carrier 26.

Rotation of the gear 24 and of the fine adjustment shaft 25 which at its right hand end (looking in the direc tion of FIG. 1) and adjacent the support 38 has the form of a threaded spindle, causes the shifting of a wedge piece 40 relatively to the support 38, whereupon a counter wedge 40' provided in the support 38 is moved perpendic ularly thereto, said counter wedge 40 constituting a sup port for the roller 38' pressing against the supporting surface 34 of the lever 31.

Thus the fine setting of the grinding disk is carried out by swinging the grinding disk carrier 26, while the rough setting takes place by means of the spindle 11. e

For mechanical rough adjustment of the present invention the grinding disk carrier 26 is provided with a direct current motor 41 having a powerful field, so that it can be regulated within a wide range; the motor 41 drives a shaft 44 through a worm drive 42 and another worm ,7

drive 43. The shaft 44 actuates the gear 17 through a coupling 45 and a toothed wheel 46. As already stated, the gear 17 may be also operated by the hand wheel 16 for the rough manual adjustment.

indicator 49 for the potentiometer setting and next to it is an indicator 50 showing the output of the main motor (not shown) which is used for driving the grinding disk 27. An indicator device 51 is used to show the speeds of rotation of the grinding disk, while an indicator device 52 is used for setting the bulge-turning device.

It is apparent that the example shown above has been given solely by way of illustration and not by Way of limitation and that it is capable of many variations and modifications within the scope of the present invention.

What is claimed is:

In a roller grinding machine having a movable upper support, a feed spindle actuating said upper support, a

grinding disk and a carrier carrying said grinding disk;

A potentiometer 47 is used to set the speed of rotation of the motor 41. Close to and to the right of the potentiometer 47 (looking in the direction of FIG. 1) is located an indicator 48 for the fine adjustment, close to it is an an apparatus for compensating the wear of the grinding disk, said apparatus comprising a shaft carried by said upper support and carrying said carrier, said carrier being swingable about said shaft, a lever pivoted to said upper support and having a horizontal sliding surface, a roller carried by said lever, a ram engaging said roller, a rotary spindle carried by said carrier, another support engaging said spindle and movable thereby, another roller carried by said other support and rolling upon said horizontal sliding surface of the lever to swing said carrier for the fine setting of the grinding disk, a hand wheel, a threaded fine adjustment shaft, means operatively connecting said hand wheel with said threaded fine adjustment shaft, 21 wedge piece movable by said threaded fine adjustment shaft, and a counter wedge carried by said other support and engaging said wedge piece, whereby said other sup port is actuated by the turning of said hand wheel.

Grifiing Feb. 15, 1938 Hall Aug. 8, 1939 

